which fuel sender

[Junk]

This is for my 77 45. It's been using an aux tank in the bed but I'd like to ditch that setup. I had originally bought a new 77 40 tank only to realize that it was just too big for the 45. So now I have a tank from what I believe to be a 64 40. It has the threaded fuel line port on the side etc. Anyway, which fuel sender would I need for this? Would the 64 fuel sender work with my current 77 guage, or is it possible that a 77 sender would work in the older tank ... or did I simply swap one problem for another?

 

[Fast Eddy]

So now I have a tank from what I believe to be a 64 40. It has the threaded fuel line port on the side etc. Anyway, which fuel sender would I need for this?

That's a tough one. You'll probably have to go with a generic replacement of some kind and fiddle around getting the ohms range to match your gauge. It might save you some frustration to get the original tank for which the sending unit is still available.

 

[Downey]

Your problem should not be that tuff. Your stock dash gauge requires a 120 ohm empty, 17 ohm full sending unit (which is actually a 9/72-newer sender), which should fit your older tank with no problem.

 

[malcb]

Hi,

I am looking at a sender which is 240 ohm empty, 20 ohm full. Seems to be a standard range. If I put a 120 ohm resistor across the terminals I think I will get 120 ohm empty and aroun 18 ohm full, anyone confirm I am right?

 

[Fast Eddy]

I am looking at a sender which is 240 ohm empty, 20 ohm full. Seems to be a standard range. If I put a 120 ohm resistor across the terminals I think I will get 120 ohm empty and aroun 18 ohm full, anyone confirm I am right?

1/Rtotal = 1/R1 + 1/R2
1/Rt = 1/240 + 1/120
1/Rt = 3/240
Rt = 240/3 = 80

Working the other way:

1/120 = 1/240 + 1/R
2/240 = 1/240 + 1/R
1/240 = 1/R
R=240 = what you need in parallel to get it right.

When full using the above 240 ohm value in parallel:

1/Rfull = 1/240 + 1/20
1/Rf = 13/240
Rf = 240/13
Rf = 18.5 = close enough.

 

[Junk]

Your problem should not be that tuff. Your stock dash gauge requires a 120 ohm empty, 17 ohm full sending unit (which is actually a 9/72-newer sender), which should fit your older tank with no problem.

Very cool. Thanks for the help.